tbuckley/cabot-search huggingface dataset:
Abstract 6359: Structural insights into Siglec-15 reveal glycosylation dependency for interaction with T cells through integrin CD11b
Authors: Maria Pia Lenza, Leire Egia-Mendikute, Asier Antoñana-Vildosola, Cátia O. Soares, Francisco Corzana, Iker Oyenarte, Filipa Marcelo, Jesús Jiménez-Barbero, June Ereño-Orbea, Asis Palazon
Journal: Cancer Research (2023)

Abstract Sialic acid-binding Ig-like lectin 15 (Siglec-15) is emerging as an immune modulator and target for cancer immunotherapy. However, limited knowledge regarding the mechanism of action, structure and binding partners on T cells restrains the development of drug candidates that unleash its full therapeutic potential. Here, we solve the crystal structure of Siglec-15 and delineate its binding epitope by co-crystallization with an anti-Siglec-15 blocking antibody. Saturation transfer-difference (STD) nuclear magnetic resonance (NMR) spectroscopy assisted with molecular dynamic simulations revealed the binding mode of Siglec-15 to the cancer-associated sialyl-Tn (sTn) glycoform. Binding of Siglec-15 to T cells, which lack sTn expression, depends on the presence of sialic acid. We identified the leukocyte integrin CD11b as a binding partner of Siglec-15 on human T cells. Collectively, these data provide an integrative understanding of the structural features of Siglec-15 and underscore glycosylation as an additional layer of control of T cell responses. Citation Format: Maria Pia Lenza, Leire Egia-Mendikute, Asier Antoñana-Vildosola, Cátia O. Soares, Francisco Corzana, Iker Oyenarte, Filipa Marcelo, Jesús Jiménez-Barbero, June Ereño-Orbea, Asis Palazon. Structural insights into Siglec-15 reveal glycosylation dependency for interaction with T cells through integrin CD11b [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6359.
Abstract 5464: Predictive biomarkers for PD-1 and PD-L1 checkpoint inhibitor response in NSCLC: An analysis of clinical trial and real-world data
Authors: WeiQing Venus So, David Dejardin, Eva Rossmann, Jehad Charo
Journal: Cancer Research (2023)

Abstract Importance: Largest analysis combining clinical trial and real-world data (RWD) to assess the clinical utility of biomarkers for anti-PD-1/PD-L1 checkpoint inhibitors (CPI) in NSCLC patients. Objective: To assess the association between tumor PD-L1, TMB and blood analytes with clinical outcomes in patients with advanced NSCLC following CPI therapy. Design: Retrospective cohort study with patients stratified into high and low biomarker groups. Correlation with treatment outcome in the different biomarker groups was investigated and compared between patients treated with CPI versus chemotherapy. Setting: Data derived from electronic health records mostly from community oncology settings were combined with clinical trial data. Participants: Starting with 71850 patients with advanced NSCLC who received CPI or chemotherapy, we selected 24152 patients from an electronic health record-derived de-identified NSCLC clinicogenomic database (CGDB) from a real-world cohort and nine Roche atezolizumab trials. Patients were diagnosed between January 2011 and February 2020 (data collection cut-off date). Main Outcomes and Measures: Drug response was assessed by RECIST criteria for clinical trials and real-world response for RWD. Durable response was defined as having CR/PR without progression during the study period of 270 days. Associations of biomarker levels with treatment outcomes were analyzed using Fisher’s exact test. Results: High expression of PD-L1 on tumors (≥50%) were associated with lower risk of resistance to CPI (odds ratio [OR] 0.21; 95% CI = 0.14, 0.32; P&amp;lt; .001). The association was stronger in patients who had prior chemotherapy than first line CPI, with non-squamous than squamous histology, and smokers than non-smokers. Higher TMB (≥9.57 mut/Mb) was also associated with durable response (OR = 0.41; CI = 0.30, 0.55; P&amp;lt; .001). The combination of high TMB and PD-L1 expression was the strongest predictor of durable response (OR = 0.04; CI = 0.00, 0.20; P&amp;lt; .001). There was no evidence of an association between PD-L1/TMB and response to chemotherapy, suggesting a CPI-specific predictive effect. In contrast, blood analytes were prognostic, having correlation with clinical outcome irrespective of treatment type. Conclusion: This study supports the predictive utility of PD-L1 expression and TMB for NSCLC patients receiving CPI therapy and further elucidates their utility in patient sub-populations. Citation Format: WeiQing Venus So, David Dejardin, Eva Rossmann, Jehad Charo. Predictive biomarkers for PD-1 and PD-L1 checkpoint inhibitor response in NSCLC: An analysis of clinical trial and real-world data. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5464.
Abstract 6296: Preclinical study of a novel anti-CLEC12A antibody-drug conjugate with a glucuronide-protected pyrrolobenzodiazepine payload
Authors: Jinwon Jung, Juhee Kim, Bora Lee, Jung A Kwon, Suyoun Lee, Byeongmin Yoo, Minji Ko, Ilhwan Ryu, Donghoon Yeom, Kyoungjae Lee, Jaehyun Eom, Hanbyul Lee, Jinhyung Ahn, Eunsil Sung, Weonkyoo You, Sang Hoon Lee, Myeong Joo Kim, Keon Woo Kwon, Hyun Joo Bae, Yun-Hee Park, Ho Young Song, Chul-Woong Chung
Journal: Cancer Research (2023)

Abstract C-type lectin domain family 12 member A (CLEC12A, CLL-1) is a single-pass transmembrane protein of 265 amino acids that is found on monocytes and AML blasts. We have created and characterized antibody-drug conjugates (ADCs) based on a humanized CLEC12A specific antibody to determine whether CLEC12A may be exploited as a therapeutic target for AML. The payload is a proprietary PBD prodrug with a beta-glucuronide trigger, and the linker-payload was conjugated through farnesyltransferase-mediated functionalization. The ADC demonstrated sub-nM cytotoxicity in vitro against several CLEC12A-positive cell lines including HL-60 and PL21. Leu234Ala/Leu235Ala (LALA) mutations were employed to reduce Fc gamma receptor binding and to avoid on-target toxicity. The LALA mutation-bearing ADC displayed a nearly 50-fold decrease in cytotoxicity towards CD34+ hematopoietic stem cells. Its potency was reduced but still sufficient with IC50 values of 61 pM and 15 pM against HL60 and PL21, respectively. Regardless of LALA mutation, the ADCs demonstrated potent antitumor activities with a complete regression at a dose of 0.5 mpk against a subcutaneous HL-60 SCID mouse xenograft model. When the LALA-mutated ADC was tested against a disseminated NSGA mouse model of HL-60-luc, all treated animals survived without clinical symptoms for three weeks after treatment, whereas vehicle-treated animals exhibited morbidity 19 days after treatment or 35 days after tumor implantation. The bone marrow of ADC-treated animals appeared to have nearly fully recovered, whereas that of vehicle-treated animals showed necrosis or tumor growth. In cynomolgus monkeys, the LALA-mutated ADC had a half-life of 82 hours at a dose of 0.2 mpk, and target-mediated drug disposition appeared weak or negligible. Our preclinical studies have shown that CLEC12A targeting ADC can be used as a therapeutics for treating AML. Citation Format: Jinwon Jung, Juhee Kim, Bora Lee, Jung A Kwon, Suyoun Lee, Byeongmin Yoo, Minji Ko, Ilhwan Ryu, Donghoon Yeom, Kyoungjae Lee, Jaehyun Eom, Hanbyul Lee, Jinhyung Ahn, Eunsil Sung, Weonkyoo You, Sang Hoon Lee, Myeong Joo Kim, Keon Woo Kwon, Hyun Joo Bae, Yun-Hee Park, Ho Young Song, Chul-Woong Chung. Preclinical study of a novel anti-CLEC12A antibody-drug conjugate with a glucuronide-protected pyrrolobenzodiazepine payload [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6296.
Abstract 6343: 7E1, a novel blocking antibody targeting human anti-Müllerian-hormone-receptor II (AMHRII), elicits potent anti-tumor activity <i>in vivo</i>
Authors: Yongfei Yang, Huilin Li, Hao Li, Yue Yan, Jianhui Li, Qingcong Lin, Huijun Yin, Xiangshan Zhou, Miao Zhang, Kunbao Wu, Leqiao Sun, Shan Zhong
Journal: Cancer Research (2023)

Abstract Anti-Müllerian hormone (AMH), is a TGF-β family autocrine hormone and cognate ligand for the type II AMH receptor (AMHR2). AMH signaling through AMHR2 plays an important role in fetal sexual development by inducing Müllerian duct regression in males. AMHR2 is aberrantly expressed in various human malignancies, including colon, testis, gastric, and ovarian cancers. Functionally, AMH has complex effects on cell cycle regulation; at physiological concentrations it promotes survival and chemoresistance of cell lines, whereas at supraphysiological concentrations it inhibits tumor cell viability. Like other TGF-β family members, binding of its target receptor effects changes in gene expression through activation of intracellular SMAD, NF-κB, and Akt signaling. We developed a fully human anti-AMHR2 monoclonal antibody, 7E1, from RenMab™ mice, which contain the full human immunoglobulin variable domain. 7E1 was found to contain a distinct binding epitope associated with efficient inhibition of AMH binding and signaling. 7E1 also displayed a better ADCC effect than the reference AMHR2 antibody. The in vivo half-life of 7E1 in AMHR2- and FcRn-humanized mice exceeded the reference antibody as well and is in a desirable range from a development perspective. To evaluate the safety and efficacy of 7E1 in vivo, we established syngeneic murine tumor models in AMHR2-humanized mice. We found that 7E1 monotherapy significantly inhibited tumor growth in a dose-dependent manner. Moreover, 7E1 was well tolerated in mice, and no adverse effects were observed even at extremely high doses (e.g. 100 mg/kg). Taken together, these data demonstrate that 7E1 is a novel anti-human AMHR2 blocking antibody with desirable pharmacokinetic and pharmacodynamic properties. 7E1 may potentially find broad application for a range of cancer indications in which AMH signaling is implicated. Citation Format: Yongfei Yang, Huilin Li, Hao Li, Yue Yan, Jianhui Li, Qingcong Lin, Huijun Yin, Xiangshan Zhou, Miao Zhang, Kunbao Wu, Leqiao Sun, Shan Zhong. 7E1, a novel blocking antibody targeting human anti-Müllerian-hormone-receptor II (AMHRII), elicits potent anti-tumor activity in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6343.
Abstract 6371: Identification of a <i>lymphocyte activation gene-3</i>-binding peptides using phage displayed-peptide libraries for cancer immunotherapy
Authors: Seok-Min Lee, Byungheon Lee
Journal: Cancer Research (2023)

Abstract Treatment with immune checkpoint blockades against CTLA-4, PD-1, and PD-L1 is currently giving improved results to many cancer patients. Nevertheless, a significant proportion of cancer patients treated with immune checkpoint blockades are still largely unsatisfied with the benefits of these drugs. One of the reasons is that cancer cells also use other immune checkpoints such as lymphocyte activation gene-3 (LAG-3), T cell immunoreceptor with Ig and ITIM domains, and T-cell immunoglobulin and mucin-domain containing-3. In this study, we screened phage displayed-peptide libraries for peptides that selectively bind to LAG-3. After five rounds of screening, we selected a candidate peptide and named it LAG3Pep. LAG3Pep preferentially bound to human LAG-3-transfected HEK 293T cells over mock-transfected cells and phorbol myristate acetate/ionomycin/chloroquine-stimulated Jurkat T cells over unstimulated cells. LAG3Pep also bound to splenocytes isolated from tumor-bearing mice, suggesting the reactivity across human and mouse LAG-3. Pull-down assay of human recombinant LAG-3 protein using biotin-labeled LAG3Pep yielded a protein band of LAG-3. LAG3Pep showed a high-affinity binding to the LAG-3 protein in SPR assays. Pre-treatment of a LAG-3-blocking antibody competed the binding of LAG3Pep to stimulated Jurkat T cells. LAG3Pep inhibited the binding of the LAG-3 protein to THP-1 cells expressing HLA-DR, a well-known LAG-3 ligand. In addition, treatment of T-cells with LAG3Pep in combination with a PD-L1-blocking antibody recovered the secretion of IL-2 by T-cells which was suppressed by FGL-1, another ligand of LAG-3, secreted from HepG2 tumor cells in co-culture. Intravenous administration of LAG3Pep in combination with a PD-L1-blocking peptide showed an anti-tumor growth activity in the MC38 syngeneic mouse colon tumor model. These results show that LAG3Pep acts as LAG-3 blockade and, in combination with a PD-L1-blockade, could be a promising tool for cancer immunotherapy. Citation Format: Seok-Min Lee, Byungheon Lee. Identification of a lymphocyte activation gene-3-binding peptides using phage displayed-peptide libraries for cancer immunotherapy. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6371.
Abstract 1840: Methylmalonic acid accumulation suppresses CD8+ T cell activation and contributes to age-induced immunosuppression
Authors: Joanne D. Tejero, Stanislav Drapela, Juan Fernandez-Garcia, Sarah-Maria Fendt, Didem Ilter, Ana P. Gomes
Journal: Cancer Research (2023)

Abstract Deregulation of cytotoxic CD8+ T cells is a feature of the aging process with important consequences for anti-tumor immunity and consequently affects tumor initiation, progression, and response to immunotherapies. However, our understanding of how the aging process affects CD8+ T cells remains incomplete. Vitamin B12 deficiency is also a feature of old age caused by a well-recognized decrease in vitamin absorption. Interestingly, clinical studies have reported a significant decline in CD8+ T cells in individuals with vitamin B12 deficiency, suggesting that vitamin B12 levels might be a mechanistic link between aging and deregulation of CD8+ T cells. An important and often overlooked consequence of vitamin B12 deficiency is an elevation of methylmalonic acid (MMA) in circulation. Our laboratory has previously established a critical role for age-induced MMA in promoting progression into metastatic disease of breast and lung cancers, which coincided with a robust immunosuppressive signature. Here, we demonstrate that exposure of CD8+ T cells to MMA or culture of CD8+ T cells in the absence of vitamin B12 reduces T cell activation, thereby decreasing T cell numbers and effector function. Conversely, supplementation of vitamin B12 on CD8+ T cells isolated from old mice enhances their ability to activate and increases T cell numbers. Evaluation of the effects of MMA on the CD8+ T cells metabolome revealed a decrease in antioxidant levels, including a pronounced reduction in vitamin C and reduced glutathione, which were accompanied by an increase in both superoxide and hydrogen peroxide, suggesting that an increase in reactive oxygen species might be the link between MMA and CD8+ T cell dysfunction. Together, these results put forward the idea that MMA is an important regulator of immune cell function and that supplementation of vitamin B12 in older people and individuals diagnosed with vitamin B12 deficiency may function as an important strategy to improve immune cytotoxic responses and thereby increase anti-cancer immunosurveillance and the effectiveness of certain immunotherapies. Citation Format: Joanne D. Tejero, Stanislav Drapela, Juan Fernandez-Garcia, Sarah-Maria Fendt, Didem Ilter, Ana P. Gomes. Methylmalonic acid accumulation suppresses CD8+ T cell activation and contributes to age-induced immunosuppression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1840.
Abstract 3161: Novel gene signature for predicting aggressive type of bladder cancer and the associated therapeutic strategies
Authors: Jim Jinn-Chyuan Sheu, Chung Chang, Bo-Chen Lin, Tritium Hwang
Journal: Cancer Research (2023)

Abstract We have previously developed a unique HD-MAC (high-dimensional analysis of molecular alterations in cancer) platform that enables us to define independent tumor biomarkers from a group of clinically-significant genes. Using this platform, 26 genes were identified as independent prognosis biomarkers whose overexpression determine shorter overall survivals in patients with bladder cancer. Through clinical association study (including tumor stage, lymph node invasion, angiogenesis, and metastasis), a gene signature containing 6 biomarkers was established which can be validated by two independent cohorts. Gene knock down effects on cancer cell survival further revealed PPT2 and PRPF19 as potential targets for target-based therapy. Correlation study between genetic dependencies and drug sensitivities across cell lines suggested several potent lead compounds which are likely to function through similar mechanisms of gene effect actions. Our study therefore provides newly defined prognostic biomarkers as well as the associated therapeutic strategies for possible clinical applications in patients with bladder cancer. Citation Format: Jim Jinn-Chyuan Sheu, Chung Chang, Bo-Chen Lin, Tritium Hwang. Novel gene signature for predicting aggressive type of bladder cancer and the associated therapeutic strategies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3161.
Abstract 1853: Microparticle-delivered Cxcl9 prolongs Braf inhibitor efficacy in melanoma
Authors: Gabriele Romano, Francesca Paradiso, Peng Li, Pooja Shukla3, Lindsay Barger, Olivia El Naggar, John P. Miller, Roger J. Liang, Timothy L. Helms, Jennifer A. Wargo, Francesca Taraballi, James C. Costello, Lawrence N. Kwong
Journal: Cancer Research (2023)

Abstract Patients with BRAF-mutant melanoma show significant responses to combined BRAF and MEK inhibition, but most patients relapse within 2 years. A major reservoir for such drug resistance is minimal residual disease (MRD), which is comprised of drug-tolerant tumor cells laying in a dormant state. Towards exploiting potential therapeutic vulnerabilities of MRD, we established a genetically engineered mouse model of BrafV600E-driven melanoma MRD wherein genetic BrafV600E extinction leads to strong but incomplete tumor regression. Transcriptional time-course analysis of tumors after BrafV600E extinction revealed that after an initial surge of immune activation, tumors later became immunologically "cold" after MRD establishment. Computational analysis identified candidate T-cell recruiting chemokines that may be central players in the process, being strongly upregulated initially and then steeply decreasing as the immune response faded. As a result, we hypothesized that sustaining the chemokine signaling could impair MRD maintenance through increased recruitment of effector T-cells. We show that intratumoral administration of recombinant Cxcl9, either naked or loaded in microparticles, significantly impaired the relapse of MRD in BRAF-inhibited tumors, including several complete pathological responses after the triple combination of microparticle-delivered rCxcl9 with BRAF and MEK-inhibition. Our experiments constitute a proof of concept that chemokine-based microparticle delivery systems are a potential strategy to forestall tumor relapse and thus improve the clinical success of frontline treatment methods. Citation Format: Gabriele Romano, Francesca Paradiso, Peng Li, Pooja Shukla3, Lindsay Barger, Olivia El Naggar, John P. Miller, Roger J. Liang, Timothy L. Helms, Jennifer A. Wargo, Francesca Taraballi, James C. Costello, Lawrence N. Kwong. Microparticle-delivered Cxcl9 prolongs Braf inhibitor efficacy in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1853.
Abstract 2101: Cancer-associated fibroblast activation predicts progression, metastasis, and prognosis of cutaneous squamous cell carcinoma
Authors: Jaakko S. Knuutila, Pilvi Riihilä, Liisa Nissinen, Roosa Kallionpää, Teijo Pellinen, Veli-Matti Kähäri
Journal: Cancer Research (2023)

Abstract Purpose: Cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer and the metastatic disease is associated with poor prognosis. At present, no established biomarkers are available for predicting the metastasis risk and prognosis of patients with cSCC. Cancer-associated fibroblasts (CAFs) promote the progression of cancer, but their role in cSCC is largely unknown. Here, we have examined the potential of CAF markers in the assessment of metastasis risk and prognosis of primary cSCC. Experimental Design: We utilized multiplexed fluorescence immunohistochemistry for profiling of CAF landscape in metastatic and non-metastatic primary human cSCCs, the actual metastases, and in premalignant and benign epidermal lesions. Quantitative high-resolution image analysis was performed with two separate panels of antibodies for CAF markers and the results were correlated with clinical and histopathological parameters including disease-specific mortality. Results: Increased stromal expression of fibroblast activation protein (FAP), α-smooth muscle actin, and secreted protein acidic and rich in cysteine (SPARC) were associated with progression of premalignant epidermal lesions to invasive cSCC. Furthermore, elevation of FAP and platelet-derived growth factor receptor-β (PDGFRβ) expression was associated with the risk of metastasis of primary cSCCs. High expression of PDGFRβ and periostin correlated with poor prognosis. Furthermore, a multi-marker defined CAF subset, PDGFRα-/PDGFRβ+/FAP+, was associated with invasion and metastasis and independently predicted poor disease-specific survival. Conclusions: These results show, that fibroblast activation evolves during the progression of cSCC. High PDGFRβ expression alone and multimarker combination PDGFRα-/PDGFRβ+/FAP+ are potential biomarkers for the progression of primary cSCC to metastatic stage, and for poor prognosis. Citation Format: Jaakko S. Knuutila, Pilvi Riihilä, Liisa Nissinen, Roosa Kallionpää, Teijo Pellinen, Veli-Matti Kähäri. Cancer-associated fibroblast activation predicts progression, metastasis, and prognosis of cutaneous squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2101.